Answer:
58.7g
Explanation:
Given parameters:
Volume of solution of NaF = 508mL = 0.508dm³
Concentration = 2.75M
Unknown:
Mass of NaF used = ?
Solution:
Concentration in this regard is molarity. Molarity of a solution is the amount of solute dissolved in a solution. Here the number of moles of solute in a given volume of solution gives molarity.
Molarity = [tex]\frac{number of moles }{volume}[/tex]
Using this expression, let us find the number of moles of NaF;
Number of moles of NaF = molarity x volume
= 2.75 x 0.508
= 1.397moles
Now;
Mass of NaF = number of moles x molar mass
Molar mass of NaF = 23 + 19 = 42g/mol
Mass of NaF = 1.397 x 42 = 58.7g
